Heat interchanging apparatus



July 4, 1933. w SCHMIDT 1,916,337

HEAT INTERCHANGING APPARATUS Filed Nov. 28, 1951 2 Sheets-Shet 1 IN V ENT OR. WALT/5P ASCHMIDT l 7% ATTORNEYS.

J y 9 1933- w. A. SCHMIDT 1,916,337

HEAT INTERCHANGING APPARATUS Filed Nov. 28, 1951 2 Sheets-Sheet 2 INVENTOR. MLTEP A. SCHMIDT BYmzizw/w ATTOR EYS.

Patented July :4, 1933 UNITED STATES PATENT OF'FlCE WALTER A. SCHMIDT, OF LOS ANGELES, CALIFORNIA, ASSIGNOR TO INTERNATIONAL PRECIPITATION COMPANY, OF LOS AN CALIFORNIA GELES, CALIFORNIA, A CORPORATION 0! HEAT INTERCHANG NG APPARATUS Application filed November 28, 1931. Serial No. 577,767.

This invention relates to improvements in heat interchanging apparatus, and the main object of the invention is to increase the heatinterchanging capacity of apparatus of this character, .particularly when operating with gases containing material which tends to form a heat insulating coating on the heat interchanging walls of such apparatus. 'Such coating interferes seriously with the efficiency of the heat interchanging operation, and an important object of the invention is to provide means for .maintaining the surfaces of such apparatus in clean condition, thereby maintaining the heat interchanging effect at full efiiciency.

Another object of the invention is to pro vide for bringing the gas or fluid which is subjected to the heat interchanging operation into more eifective contact or heat interchanging relation with the heat interchanging walls.

The accompanying drawings illustrate the invention, and referring thereto:

Fig. 1 is a vertical section of one form of apparatus suitable for carrying out the invention.

Fig. 2 is a section on line 2-2 in Fig. 1.

Fig. 3 is a section on line 33 in Fig. 1.

Fig. is a plan view of anotherform of the heat interchanging apparatus.

Fig. 5 is a section ,on line 55 in F ig. 4.

Fig. 6 is a side elevation, partly in section, of a form of heat interchanging apparatus adapted for effecting separation of solid suspended material concurrently with the heat interchanging operation.

Fig. 7 is a side elevation, partly insection, of a form of heat interchanger especially adapted for utilization of the heating or cooling effect on the medium passing exteriorly of the heat interchanging tubes.

7 Referring to Figs. 1 to 3, a tubular cham-.

ber formed, for example, as a cylindrical pipe 1, is connected at one end to a gas inlet 2, and is provided at the other end with means for carrying away the gas after the heat interchanging operation has been performed thereon. The tubular chamber 1 may be mounted vertically as shown, the gas inlet 2 being connected thereto at the upper end,

and the lower end of said tubular chamber being connected to a bin or hopper 3 provided gas follows asinuous, helical or vortical path 7 in passing downwardly through the tube.

My invention is particularl intended for application in connection wit the transfer of heat from or to gases containing material which is of such nature that it tends to form a coating on the wall of the heat interchanging chamber. Such a coating is generally of extremely low heat conductivity as compared to the material of which the wall of the heat interchanging chamber is generally composed, and the resulting resistance to transfer ofheat through said wall interferes Seriously with the efliciency of the heat interchanging operation. My invention comprises means for continuously or intermittently removing such a coating, and for this purpose I provide means for feeding'into the gas stream passing to the heat interchanging chamber 1, finely divided solid material adapted to act as a scouring agent. Said means may comprise a chute 6 opening into the upper end of thetube or chamber 1 and connected through feed means 7 to a bin 8 or other source of supply of finely divided solidmaterial, so as to cause such solid material to be distributed into the current of gas passing from the inlet 2 into the tube 1. The gas, which may be supplied to the apparatus from any suitable source, for example, from a furnace, drier, evaporator, 01' other meansproducing an efll'uent containin}; material which is liable to form a more or less adherent deposit on the wall of the chamber 1, passes downwardly into said trifugal action due to such vortical motion charge electrodes 12 are arranged concentricauses the solid suspended material or cally around the tubular chamber 1 and at scouring agent to be thrown outwardly such distance apart as to provide for effective against the cylindrical wall of chamber 1, electrical convection due to the electric field and b its rapid tangential or helical movedevelo d between said electrodes and the ment in contact with said wall as indicated wallo the tubular chamber 1. by the dotted line, effects the scouring or The discharge electrode system comprising cleaning action, more or less completely rethe electrodes 12 and their supporting means moving from the wall any coating which is connected by wire 21 to any suitable high tends to form thereon. By this means the tension supply line, for example, an alternatwall of the heat interchanging chamber 1 ing current line of suitable high tension voltmay be maintained in efiective heat interage, and the opposing electrode constituted changing condition. The scouring action by the tubular chamber 1 is grounded as indimay be efiected continuously, if desired, or in cated at 21' sothat an electrical field is mainsome. cases the scouring material may be tained between the electrodes 12 and the supplied intermittently so as to clean the member 1 sufiicient to cause silent electrical wall of the chamber 1 from time to time, acdischarge from the edges of electrodes 12 and cording to the requirements of the particuresulting electric convection of the air and lar case. proximity to the wall of the member 1, the The gas passes from the chamber 1 into convection currents passing from the disthe bin 3 and out through the outlet 4, the charge electrodes toward said wall and then divided solid scouring agent being mainly outwardly away from said wall in the spaces or wholly collected in the bin 3 and removed between the electrodes 12. Such convective throu h outlet means 10 at the bottom of said action largely increases the effective contact 0 bin. lhe scouring means above referred between the air surrounding the tubular to may consist of sand or other granular mam mber 1 and the Wall of said tubular memterial capable of efiecting the scouring acher, and correspondingly increases the heat tion, and such material may be sufiiciently interchanging efiect -coarse to enable substantially all of the same f fiesll d, l' lfier nay be- Incl ded 111 to be deposited in the bin 3 by th action f the high tension connection to the discharge gravity, and by the efiect of the reversal of electrodesystein so as to supply rectified or direction of the gas stream in passing upun directional current thereto, said rectifier Wardly to the outlet 4. The rapid vortical b g f a y sui a typ o exalp 1 a motion of the gas stream adjacent the wall of ani rectifier, valve yp rectl 1 a th ha b ql, i t d b th presence f th a solid contact rectifier of the copper oxide scouring material, also eliminates more or yp lesscompletely, the heat insulating effect of In ca he v lume of gas to be treated is th t ti gas fil hi h i ll presin excess of that which can conveniently be ent in immediate contact with the wall of treated 111 a r p r chamber, the th h b struction shown in igs. 4 and 5 may used,

The heat interchanging apparatus will compl'lsmg P y of Vertlcal P p generally b u d i ithd l f h t tubular chambers 33 connected at the rupper from hot gases, and in such case the heat abends to an )B 11982191 34 a at -hi agent i generally th t h i i ends to a bin 35, the inlet header 34 communino surrounding the apparatus. Any suitable eating with the P p 33 through tangential T v y means well known in the art may be employed pe Passages r b.v h 8 for increasing the circulation of such cooling lg the l P}P 33.15 glven gas so as to increase the efiective contact of gfimtlal Vortlcal E- gas flmtlet such gas with the wall of the heat interchang- P P 37 leads from the j 35 sultallle ing chamber: In some cases this increased Such as a t 38, 15 P E 9 circulation may be advantageously efiected F i fggg g g g i g ghgag g g gg g g g a; by the action of electric windage or electrical involute curved walls f d fl ting the gas convection means for this purpose being shown in 1 to 3 and .comprising disfigfi g ggzggg ggfigg z g fiat? 190 charge electrodes formed as vertical bars 12 ri a1 t 0 the apparatus for example, to the inlet mounted to swing on vertical pivot shafts 13 v 'so as to adjust the distance between the disitffifi figg 33. ga ifififig g j charges edges 12' of said bars and the outside 1g mittenfly feed-mg divided solid mug of the tubular chamber'l. The. supporting ii f a b11141 to a chute 42 which P o e 13 amimounted y l' l and char-glib said material into the gas passing 16 on ulators 1'? and 8 re p y, through the inlet 34'tothe inlet header 34. mounted on supporting means 19 and 20 at More or less finel divided solid material, to and bottom of the apparatus or in any such as sand,-or ot or material suitable for ot er suitable manner. The several di's- 'efiecting a scouringaction is supplied by the m til feeding means aforesaid to the gas enterin the inlet header 34 and passing along witfi the gas into the heat interchanging chambers 3.3 proceeds downwardly in said chambers with a rapid vortical or whirling motion and the solid material supplied to the gas partakes of such rapid vortical or whirling mo-- tion and effectively scours the inner walls of the pipes or chambers 33' with the result that any coating or deposit of material which tends to be deposited on such walls from the gas which is being treated, is secured and removed by the action of said divided solid material. The solid material usedmay be sufliciently coarse and heavy to enable it to settle in the bin 35 after the gas has passed through the heat interchanging chambers and may, if desired, be continuously or intermittently returned to the feeding means aforesaid for' re-use in the same apparatus. The gas on which the heat interchanging operation has been performed passes out through the outlet 37, and if necessary, any residual scouring material carried thereby may be removed therefrom by suitable separating means.

In case more effective separating action is required than can be efi'ected by the apparatus above described, the heat interchanging apparatus may be of the cyclone type, such as shown in Fig. 6 comprising, for example, a plurality of separating and heat interchanging tubes or chambers 44 connected at their upper ends to an inlet header 45 and at their lower end to a bin 46 provided with discharge gate ,47 for separated material. Outlet tubes 48 are located within the respective tubes or chambers 44 at the upper ends thereof and communicate with an outlet flue 49 leading to suitable means, such as blower 50, for producing the requisite rapid flow of gas through the apparatus. Suitable means such as'helical vanes 51 are provided within 7 the respective tubes or chambers 44 adjacent the inlet passages leading from the inlet header 45 to said tubes, so as to cause the gas entering the separator tubes to assume a vortical motion.

Means are provided 'for supplying divided solid material to the gases passing to' the separator tubes, said means comprising, for example, a screw conveyor 53 feeding material from a storage bin 54 to a distributor 55 which operates to disperse such material into the gas flowing through the inlet flue 56 which conducts the gas to be treated tothe inlet header 45. Said distributing means is shown as consistingof a disc rotating at high velocity by a motor 58 but the distributing means may be of any suitable construction.

- In this form of my invention the gas to bet reatedand containing material which would tend to form a coating on the walls of the heat interchanging apparatus, is supand the res ective outlet tubes 48 and is deflected by t 1e means 51 in said passages, so as to give a vortical motion which causes the suspended solid material in the gases to move rapidly over the innersurface of the tubes' or chambers 44, thereby scouring the same and preventing accumulation of heat insulating coating thereon. The vertical motion of the gas'tends to throw the suspended solid material close to the wall of the separator chambers and thereby not only assists in the scouring action but causes separation of the solid material from the gases in such manner that the solid material may be substantially wholly removed from the gases and be collected in the bin 46, while the clean gas passes out through the outlets 48. I

In any of the above described forms of th invention withdrawal of heat from the heat interchanging walls or the supply of heat thereto, as the case may be, at the outside thereof, may be effected in any suitable manner, for example, by radiation and/0r conduction through the surrounding atmosphere or by means of a fluid, either liquid or gaseous, circulated in contact with the heat interchanging chambers or by any other suitable means. The transmission of heat to or from the heat interchanging walls may, if desired, be assisted by electric convection by means of the apparatus shown in Figs. 1 to 3, but it will be understood that my invention is not limited to theuse of such apparatus. In

ing the heat interchanging pipes 61 which are connected to inlet and outlet headers 62 and 63 as above described, said casing being provided with inlet means 64 and outlet means 65 for circulating therethrough the fluid (either liquid or gaseous) to be heated or cooled. Suitable bafile means 66 may be provided for guiding the fluid in a tortuous path to cause effective contact of same with the heat interchanging pipes. Means indicated at 67 are provided for supplying divided solid scouring material to the gas passing to V the heat interchanging pipes, and a bin or hopper 68 may be provided for collecting and removing such material after the gas has passed throughthe pipes, suitable means such as tangential inlets 69 being provided motion to the gas passfor imparting vortcal 61, so as to effect the ing through the pipes scouring action above assist in separation of the from the gas.

I claim: I

1. The method of performing a heat interchanging operation upon a gas containing material which tends to form a. deposit upon the heat interchanging surfaces, which consists in supplying to such gas a divided solid scouring agent, causing the gas together with the scouring agent carried thereby to move in contact with a heat interchanging surface with sufiicient velocity to remove therefrom material deposited thereon from the gas, and maintaining said surface at a temperature different than that of said gas.

2. The method of performing a heat interchanging operation upon a gas containing material tending to deposit a coating on the heat interchanging surfaces, which consists in supplying divided solid scouring material to such gas imparting rapid vortical motion to the gas while causing the same to move in contact with a heat interchanging surface in such manner as to bring the solid material by centrifugal action into effective scouring contact with the heat interchanglng surface, so as to main ain such surface free of deposited coating and maintaining said surface at a temperature different than that of said scouring materials 3. Apparatus for heat interchanging comprising a heat interchanging chamber provided with gas inlet and gas outlet means, and means supplying divided solid scouring material to the gas entering said chamber in such manner as to cause said scouring material to be carried by the gas stream into scouring contact with the walls of said chamber, an means for maintaining said walls at a temperature different than that of the gas delivered through said inlet means.

4. A heat interchanging apparatus comprising a heat interchanging chamber proand a gas outlet means,

vided with a gas inlet said gas inlet means being constructed and adapted to produce vortical motion of the gas within said chamber, means for supplying divided solid scouring material to the gas entering said chamber in such manner as to cause said scouring material to be carried b the gas stream into scouring contact wit the walls of said maintaining said walls at such temperature as to effect heat interchange between said walls and the gas within said chamber.

5. A construction as set forth in claim 4 and comprising, in addition, means for separating the divided solid scouring material from the gas.

6. The method of performing a heat inter changing operation, which comprises main taining a heat interchanging insulating fluid described and also chamber, and means for in contact with heat interchanging surface, maintaining said surface at a temperature difierent than that of said fluid, and producing convection currents in said fluid by the action of an electrostatic field, in such manner as to increase the heat interchanging effect between said fluid and the heat interchanging surface.

.7. The method of performing a heat interchanging operation, which comprises passing a gas in contact with one side of a heat interchanging wall, maintaining a heat interchanging insulating fluid, at a temperature different than that of said gas, in contact withv the other side of said wall, and producing convection currents in said fluid by the action of an'electrostatic field, in such manner as to increase the rate of heat interchange between said fluid and said wall.

8. The method of performing a heat interchanging operation upon a gas containing material which tends to form a deposit upon heat interchanging surfaces, which consists in supplying to such gas a d ided solid scouring material, causing the as together with the scouring agent carried thereby to move in contact with one side of a heat interchanging wall with sufficient velocity to remove from said wall material deposited thereon from the gas, by the securing action of said material, maintaining a heat interchanging insulating 'fluid at a temperature different than that of said gas in contact with the other side of said wall, and producing convection currents in said fluid by the action of an electrostatic field, in such manner as to increase the heat interchanging effect between said fluid andsaid wall.

9. A heat interchanging apparatus comprising a wall, one side of which is exposed to cont-act with an insulating fluid adjacent the same, means for passing a gas at a temperature different than that of said fluid in contact with the other side of said wall, electrode means spaced from said one side of the wall and separated therefrom by said insulatin fluid, and means for maintaining a hig potential difference between said electrode means and'said wall so as to produce electrical convection in said fluid between said electrode means and said wall.

10. A heat interchanging a paratus comprising a heat interchanging c amber havin a wall, the exterior of said wall being exposed to contact with the atmosphere surrounding the same, means for passing a as at a temperature difierent than that of said atmosphere through said chamber and in contact with the interior of said wall, electrode means mounted adjacent and spaced from the exterior of said wall, and means for maintaining a high potential difference between said electrode means and said wall so as to produce electrical convection in the atmosphere therebetween.

11. A heat interchanging apparatus comprising a heat interchanging wall, means for passing a gas in contact with said wall, means for supplying divided solid scouring material to said gas in such manner as to cause said scouring material to be carried by said gas into scouring contact with said Wall, and means for maintaining said wall at a temperature difierent than that of said gas.

- 12. A heat interchanging apparatus comprising a heat interchanging wall, one side of which is exposed to contact with a heat interchanging insulating fluid adjacent said wall, means for passing a gas at a temperature different than that of said fluid in contact with the other side of said wall, means for supplying divided solid scouring material to said gas in such manner as to cause said scouring material to be carried by the gas into scouring contact with said other side of the wall, elec- 1931. a WALTER A. SCHMIDT. 

